Background and objective: Asbestos can cause various pulmonary diseases including asbestosis, pleural plaques and pleural thickening. Animal and in vitro studies suggest that the toxicity of asbestos is due to the iron content of the fibres which not only generate oxidants directly, but also activate the inflammatory cells in the lung that contribute to oxidative stress. This study therefore sought to establish data in man to corroborate the animal and in vitro evidence. Exhaled breath condensate (EBC) collection is a novel, non-invasive technique to collect samples from the lung for investigating inflammatory biomarkers of lung diseases. This technique is harmless, rapid and easily repeatable which leads itself to the investigation of lung diseases such as asbestos-related diseases and pulmonary fibrosis (PF) that are otherwise difficult to study. The hypothesis tested was that oxidative and nitrosylative stress markers will be elevated in the EBC of patients with asbestos-related diseases and PF compared to normal control subjects. Methods: The study design was a cross-sectional and observational in vivo study whereby EBC was collected and fractional exhaled nitric oxide (FeNO) and carbon monoxide (eCO) were measured. EBC markers including pH, hydrogen peroxide (H2O2), total nitrogen oxides (NOx), 3-nitrotyrosine (3-NT), 8-isoprostane (8-iso), total protein and transforming growth factor-β1 (TGFβ1) were measured by microelectrode analysis, colorimetric and enzyme immunoassays. 3-NT and 8-iso were further examined by immunohistochemical techniques in samples of lung tissue. Results: Subjects with asbestosis had significantly raised levels of EBC H2O2, 8-iso, total protein and FeNO compared with healthy individuals. The same markers except H2O2, but with 3-NT and eCO were again significantly increased in those with other causes of PF, compared with control subjects. Heavy nitrotyrosine staining was found on the lung sections from patients with asbestosis and PF. Conclusions: This study confirmed that increased production of reactive oxygen and nitrogen species is associated with asbestos exposure and pulmonary fibrosis in vivo confirming animal and in vitro studies. Analysis of EBC may prove a useful non-invasive tool in exploring the basic pathophysiology of lung diseases in clinical research and may in the future be used to monitor progress in asbestosis and pulmonary fibrosis.

Thesis (M.S.)--West Virginia University, 2010. / Title from document title page. Document formatted into pages; contains ix, 52 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 49-51).

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In gas-condensate reservoirs, gas productivity declines due to the increasing accumulation of liquids in the near wellbore region as the bottom-hole pressure declines below the dew point pressure. This phenomenon occurs even in reservoirs containing lean gas-condensate fluid. Various methods were addressed to remediate the productivity decline, for example, fracturing, gas injection, solvent injection and chemical treatment. Among them, gas injection techniques have been used as options to prevent retrograde condensation by vaporizing condensate and/or by enhancing condensate recovery in gas-condensate reservoirs. It is of utmost importance that the behavior of liquid accumulation near the wellbore should be described properly as that provides a better understanding of the productivity decline due to the originated from impaired relative mobility of gas. In this research, several gas injection techniques were assessed by using compositional simulators. The feasibility of different methods such as periodic hot gas injection and gas reinjection using horizontal wells were assessed using different reservoir fluid and injection conditions. It is shown that both the temperature and composition of the injection fluids play a key role in the remediation of productivity and condensate recovery. The combined effect of these parameters were investigated and the resulting impact on gas and condensate production was calculated by numerical simulations in this study. Design parameters pertaining to field development and operations including well configuration and injection/production scheme were also investigated in this study along with the above parameters. Based on the results, guidelines on design issues relating gas injection parameters were suggested. The various simulation cases with different parameters helped with gaining insight into the strategy of gas injection techniques to remediate the gas productivity and condensate recovery. / text

This thesis has been performed at Mondi kraft pulp and paper mill located in Sweden, Kramfors Dynäs due to the low return rate of condensate. Currently, the return rate is only at 65 - 75 %. This is problematic as the demineralization process is operating on full capacity and thus requires a reduced make-up water need. The production of demineralized water is an expensive process due to large requirements of chemicals and pump-energy, but also due to the cost of raw water and maintenance. Therefore the purpose of the work was to investigate the possibility to increase the condensate return rate and thus reduce the need of make-up water. The investigation was performed during normal production rates to simplify the interpretations. The steam and condensate system was mapped and extracted flows were identified, measured and marked on map. The extracted flows were investigated in more detail and characterized as either consumed in a process or lost to sewer or atmosphere. In the work, both minor and major improvements were investigated. Minor improvements are accomplished with small intervention measures and could be done with small or no investments costs. Major improvements require large investments costs and further investigations. Six different processes were found to constitute the total production of make-up water. These are the free blowing of excess steam, soot blowing steam, paper machine 6, de-aerating process in the feed water tanks, digester process and steam- & condensate leaks along the pipe network. Improvements with the category of minor were found to reduce steam and condensate consumption by 22 - 23 ton/h. This implies a reduction by 30 - 32 % of the added make-up water, including an annual financial benefit of 3,3 - 3,9 MSEK. Additionally 0,41 - 0,82 MSEK could be gained annually by improving the insulation on the cylinder dryer heads. The make-up water would be further reduced if insulation jackets and inspection programs were implemented on equipments along the steam lines. Two major improvements are recommended. The first major improvement involves elimination of the free blowing of excess steam. This could be accomplished by drying the bark before combustion. The added make-up water would be reduced by 25 % and with the possibility to sell the dried bark during low steam production. The second major improvement involves the digester process, where the consumptions of medium pressure steam could be reduced by replacing steam with liquor-steam from the strong liquor accumulator. Medium pressure steam could instead be converted into electricity by the turbine.

In the last decade, shale reservoirs emerged as one of the fast growing hydrocarbon resources in the world unlocking vast reserves and reshaping the landscape of the oil and gas global market. Gas-condensate reservoirs represent an important part of these resources. The key feature of these reservoirs is the condensate banking which reduces significantly the well deliverability when the condensate forms in the reservoir below the dew point pressure. Although the condensate banking is a well-known problem in conventional reservoirs, the very low permeability of shale matrix and unavailability of proven pressure maintenance techniques make it more challenging in shale reservoirs. The nanoscale range of the pore size in the shale matrix affects the gas flow which deviates from laminar Darcy flow to Knudsen flow resulting in enhanced gas permeability. Furthermore, the phase behaviour of gas-condensate fluids is affected by the high capillary pressure in the matrix causing higher condensate saturation than in bulk conditions. A good understanding and an accurate evaluation of how the condensate builds up in the reservoir and how it affects the gas flow is very important to manage successfully the development of these high-cost hydrocarbon resources. This work investigates the gas Knudsen flow under condensate saturation effect and phase behaviour deviation under capillary pressure of gas-condensate fluids in shale matrix with pore size distribution; and evaluates their effect on well productivity. Supplementary MATLAB codes are provided elsewhere on OpenAIR: http://hdl.handle.net/10059/2145.

A critical issue in the development of gas condensate reservoirs is accurate prediction of well deliverability. In this investigation a procedure has been developed for accurate prediction of well production rates using semi-empirical approach. The use of state of the art fine grid numerical simulation is time consuming and computationally demanding, therefore not suitable for real time rapid production management decisions required on site. Development of accurate fit-for-purpose correlations for fluid property prediction below the saturation pressure was a major consideration to properly allow for retrograde condensation, complications of multiphase flow and mobility issues. Previous works are limited to use of experimentally measured pressure, volume, temperature (PVT) property data, together with static relative permeability correlations for simulation of well deliverability. To overcome the above limitations appropriate fluid property correlations required for prediction of well deliverability and dynamic three phase relative permeability correlation have been developed to enable forecasting of these properties at all the desired reservoir conditions The developed correlations include; condensate hybrid compressibility factor, viscosity, density, compositional pseudo-pressure, and dynamic three phase relative permeability. The study made use of published data bases of experimentally measured gas condensate PVT properties and three phase relative permeability data. The developed correlations have been implemented in both vertical and horizontal well models and parametric studies have been performed to determine the critical parameters that control productivity in gas condensate reservoirs, using specific case studies. The improved correlations showed superior performance over existing correlations on validation. The investigation has built on relevant literature to present an approach that modifies the black oil model for accurate well deliverability prediction for condensate reservoirs at conditions normally ignored by the conventional approach. The original contribution to knowledge and practice includes (i) the improved property correlations equations, (4.44, 4.47, 4.66, 4.69, 4.75, 5.21) and (ii) extension of gas rate equations, for condensate rate prediction in both vertical and horizontal wells. Standard industry software, the Eclipse compositional model, E-300 has been used to validate the procedure. The results show higher well performance compared with the industry standard. The new procedure is able to model well deliverability with limited PVT and rock property data which is not possible with most available methods. It also makes possible evaluation of various enhanced hydrocarbon recovery techniques and optimisation of gas condensate recovery.

We calculate the strange quark content of the nucleon, <N|ss|N> − <0|ss|0> using a novel method with the MILC lattice QCD gauge ensembles. The strangeness of the nucleon is related to the interaction cross section between dark matter and ordinary nuclear matter (e.g. in detectors) in many models. Previous results for this quantity suffered from uncontrolled systematic errors and/or large statistical uncertainties. The first result using our methods was the first modern calculation of the strangeness of the nucleon[76] with good control of systematic errors and reasonably small statistical errors, greatly reducing the uncertainty in dark matter detection cross sections. A refinement of this method allows for further reduction of statistical error. On the MILC Asqtad data, we obtain <N|ss|N> = 0.637(55)(stat)(74)(sys). The results obtained from this method are consistent with those obtained from other commonly-used methods applied to the MILC data. We also calculate the disconnected part of the pion-nucleon sigma term and the intrinsic charm of the nucleon using this method. The intrinsic charm has large statistical errors but is consistent with a perturbative calculation.

Healthcare costs are escalating in the U.S., with a projected 48 trillion dollars by 2021. More than ever medical researches are obligated to ensure that costly treatment modalities are safe and effective. Chronic obstructive pulmonary disease (COPD) is a costly and debilitating disease, ranked as the third leading cause of death in America. Currently, treatment for COPD consists of anti-inflammatory agents, bronchodilators, antibiotics and supplemental oxygen when hypoxemia or clinical manifestations ensue. Oxidative stress is central to the pathology of COPD. Supplemental oxygen has been substantiated as an instigator of oxidative stress; however, LFDO has not been evaluated as a mechanism of ongoing oxidative stress in individuals with COPD. Isofuran (IsoF), a biosynthetic relative of the validated oxidative stress biomarker 8-isoprostane, is preferentially synthesized during periods of increased tissue oxygen tension. This sort of specificity allows for refinement in the assessment of supplemental oxygen as a source of oxidative stress. To address this potential this study evaluated individuals diagnosed with COPD utilizing LFDO. The study also aimed to determine if IsoF possessed clinical application in predicting the standard pulmonary function test (PFT) parameters of FEV1, FVC, FEV1/FVC and FEF25-75. The exhaled breath condensate (EBC) of 52 individuals with COPD was evaluated for the presence of IsoF. An active control group not receiving LFDO (n=26) was compared to an active treatment group receiving LFDO for a minimum of 6 hrs/day (n=26). The groups showed no statistically significant demographic differences in age, gender, height, weight, ethnicity or smoking history or in the pulmonary function test parameters of FEV1, FVC, and FEV1/FVC, with the exception of the FEF25-75 (P=0.03). The active control group generated a mean EBC IsoF level of 35.81 ± 4.91 pg/ml (± SEM) compared to the active treatment group mean EBC IsoF level of 51.37 ± 8.27 pg/ml (P=0.057). Currently, no research has been conducted that defines baseline EBC IsoF levels in healthy or diseased lungs. No statistically significant differences in mean EBC IsoF levels were noted between the control and treatment groups; however, the results, in conjunction with the only two studies available utilizing EBC IsoF as an oxidative stress biomarker, may serve to provide benchmark information for future research regarding individuals with diseased lungs, specifically COPD.

Neste trabalho, estudamos o efeito da turbulência quântica na expansão livre do condensado de Bose-Einstein de 87Rb. O BEC é produzido em uma armadilha magnética tipo QUIC, em seguida o condensado é perturbado através da aplicação de um campo magnético. A superposição de campos magnéticos excita os modos coletivos em condições de baixa amplitude de excitação. No entanto para altas amplitudes de excitação, foi possível observar também outros efeitos, tais como: a variação do perfil de densidade e a diminuição na taxa de expansão dos átomos. A distribuição de momento dos átomos perturbados, indica a presença de turbulência quântica no superfluido caracterizada por uma cascata de energia dentro da faixa inercial. Os resultados da expansão livre do BEC mostram a variação do perfil de distribuição de densidade dos átomos evoluindo de um perfil Gaussiano a um perfil exponencial para altas amplitudes de excitação. O mesmo efeito foi observado ao aumentar o tempo de excitação na condição de baixas amplitudes de excitação. Além da variação do perfil de distribuição de densidade, a taxa da expansão dos átomos não perturbados é maior do que os átomos perturbados, apresentando a ocorrência de uma diminuição anisotrópica, significativa, da velocidade dos átomos durante a expansão livre. A diminuição da taxa de expansão pode estar relacionado com o fenômeno de localização durante a expansão livre dos átomos. / In this work, we study the effect of quantum turbulence on the free expansion of the Bose-Einstein condensate of 87Rb. The BEC is produced in a quic magnetic trap, then the condensate is disturbed by the application of a magnetic field. Superposition of magnetic fields excites collective modes under conditions of low amplitude of excitation. However, for high amplitudes of excitation, it was possible to observe other effects, such as: the variation of the density profile and the decrease in the rate of expansion of the atoms. The momentum distribution of the perturbed atoms indicates the presence of quantum turbulence in the superfluid characterized by a cascade of energy within the inertial band. The results of the free expansion of the BEC show the variation of the density distribution profile of the atoms evolving from a Gaussian profile to an exponential profile for high excitation amplitudes. The same effect was observed by increasing the excitation time in the condition of low excitation amplitudes. In addition to the variation of the density distribution profile, the rate of expansion of the undisturbed atoms is greater than the perturbed atoms, with the occurrence of a significant anisotropic decrease in the velocity of the atoms during free expansion. The decrease in the rate of expansion may be related to the localization phenomenon during the free expansion of the atoms.